Solid state microwave heating apparatus with stacked dielectric resonator antenna array, and methods of operation and manufacture

A microwave heating apparatus comprising:

• a chamber configured to contain a load;
• a solid state microwave energy source;
• a first dielectric resonator antenna that includes a first exciter dielectric resonator and a first feed structure in proximity to the first exciter dielectric resonator, wherein the first exciter dielectric resonator has a top surface and an opposed bottom surface, wherein the first feed structure is electrically coupled to the microwave energy source to receive a first excitation signal from the microwave energy source, and wherein the first exciter dielectric resonator is configured to produce a first electric field in response to the excitation signal provided to the first feed structure;
• and
• one or more second dielectric resonators stacked above the top surface of the first exciter dielectric resonator to form a dielectric resonator antenna array.

A method of operating a microwave system that includes a microwave generation module, the method comprising:

• producing, by the microwave generation module, a first excitation signal that is conveyed to a first radio frequency (RF) feed structure, wherein the first RF feed structure is positioned in proximity to a first dielectric resonator, and one or more second dielectric resonators are stacked over the first dielectric resonator;
• producing, by the first dielectric resonator in response to the first excitation signal conveyed by the first RF feed structure, a first electric field;
• and
• producing a second electric field, by the one or more second dielectric resonators in response to impingement of the first electric field, in response to the first excitation signal, or in response to both the first electric field and the first excitation signal, wherein the first and second electric fields are directed toward a chamber that contains a near-field load.

A method of manufacturing a microwave system, the method comprising:

• coupling a plurality of dielectric resonators together in a dielectric resonator stack, wherein the dielectric resonator stack includes a lowest, first dielectric resonator and one or more second dielectric resonators stacked over the first dielectric resonator;
• installing a substrate into a housing, wherein a radio frequency (RF) feed structure is coupled to the substrate, and wherein the housing defines a chamber that is configured as a waveguide with a blocked end;
• and
• installing the dielectric resonator stack into the housing so that the RF feed structure is in sufficient proximity to the first dielectric resonator to be capable of exciting the first dielectric resonator into resonance when the RF feed structure is supplied with a suitable RF excitation signal.